SeaBIOS - unofficial patches: advanced_bootmenu and multiple_floppies

If you'd like to add the useful floppies to your coreboot (read about them at
http://dangerousprototypes.com/docs/Lenovo_G505S_hacking#Useful_floppies ), or
to use your USB numpad for choosing a SeaBIOS boot entry, then this change is
for you! It contains two valuable patches together with a Makefile mod needed to
automatically apply these patches to a cloned SeaBIOS before its' compilation.

advanced_bootmenu: up to 35 entries (2 pages if >18), numpad support (console)
https://mail.coreboot.org/hyperkitty/list/seabios@seabios.org/thread/CKWLNTZU43SAHQ26USNFASORA2H5BXBE/

[PATCH v2] ramdisk: search for all available floppy images instead of one
https://mail.coreboot.org/pipermail/seabios/2018-December/012670.html

Patch descriptions are available at these links, and just in case here's a copy:

advanced_bootmenu: up to 35 entries (2 pages if >18), numpad support (console)

Add support for up to 35 boot menu entries (2 pages if >18). To solve the
">10" problem currently experienced by SeaBIOS users (there are no 11, 12, etc.
keys on a keyboard - so impossible to choose the last menu entries if you got
>10 entries because of multiple hard drives / secondary payloads / floppies)
- the boot menu has been extended to the letter keys. NOTE: TPM menu has been
moved from T to M letter: it is at the end of keyboard's 3rd row of letters and
"Trusted" is adjective while "Module" is a noun; alternatively could press '-'.

Also, add support for a numpad. Small USB numpad could be really convenient for
choosing the boot entries at coreboot boards used as (maybe headless) servers.
'/' char on numpad could be used to open the boot menu or to exit it. If there
are >10 boot menu entries - the numpad console interface will be enabled: press
one or two digit keys and then ENTER to confirm your choice, or remove a digit
by pressing the '.Del' key. Also you could call TPM with '-' key at any moment,
or boot with a single key press of your fullsize keyboard.

[PATCH v2] ramdisk: search for all available floppy images instead of one

All the floppy images available at CBFS will be found and listed in a boot menu,
instead of the first found. Could be highly valuable if you are participating in
a hobby OS development - would like to test multiple versions of your floppy at
the same coreboot image, to reduce the amount of re-flashes and accelerate the
development at bare metal - or simply you would like to access multiple floppies
as a coreboot user. For example: KolibriOS (nice assembly OS with GUI and apps),
FreeDOS, MichalOS, Snowdrop and memtest (coreboot's memtest version is buggy,
e.g. external USB keyboard isn't working at some laptops; floppy is much better)

Signed-off-by: Mike Banon <mikebdp2@gmail.com>
Change-Id: Idf4efba31091a8678b51c2f6541d440c5cc6d37d
---
M payloads/external/SeaBIOS/Makefile
A payloads/external/SeaBIOS/advanced_bootmenu.patch
A payloads/external/SeaBIOS/multiple_floppies.patch
3 files changed, 591 insertions(+), 1 deletion(-)